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SLV-777HF/778HF/788HF
RMT-V231B/V232B
US Model
Canadian Model
SLV-777HF/778HF/788HF
PX Model
SLV-777HF
SERVICE MANUAL
VIDEO CASSETTE RECORDER
MICROFILM
S MECHANISM
· Refer to the SERVICE MANUAL of VHS MECHANICAL
ADJUSTMENT
for MECHANICAL ADJUSTMENTS.
(9-921-647-11)
G
j
SPECIFICATIONS
Photo : SLV-788HF


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-- 2 --
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK
! OR DOTTED LINE WITH
MARK
! ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS
LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE
COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS
APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS
PUBLISHED BY SONY.
ATTENTION AU COMPOSANT AYANT RAPPORT
À LA SÉCURITÉ!
LES COMPOSANTS IDENTIFÉS PAR UNE MARQUE
! SUR LES
DIAGRAMMES SCHÉMATIQUES ET LA LISTE DES PIÈCES SONT
CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT. NE
REMPLACER CES COMPOSANTS QUE PAR DES PIÈSES SONY
DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU
DANS LES SUPPÉMENTS PUBLIÉS PAR SONY.
DIFFERENT SPECIFICATIONS
MODEL
SPECIFICATIONS
BODY COLOR
REMOTE COMMANDER
SLV-788HF
BLACK
RMT-V232B
SLV-778HF
BLACK
RMT-V231B
SLV-777HF
US, Canadian
PX
TITAN
BLACK
RMT-V231B


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SAFETY CHECK-OUT
After correcting the original service problem, perform the following
safety checks before releasing the set to the customer.
1.
Check the area of your repair for unsoldered or poorly-soldered
connections. Check the entire board surface for solder splashes
and bridges.
2.
Check the interboard wiring to ensure that no wires are
"pinched" or contact high-wattage resistors.
3.
Look for unauthorized replacement parts, particularly
transistors, that were installed during a previous repair. Point
them out to the customer and recommend their replacement.
4.
Look for parts which, though functioning, show obvious signs
of deterioration. Point them out to the customer and
recommend their replacement.
5.
Check the line cord for cracks and abrasion.
Recommend the replacement of any such line cord to the
customer.
6.
Check the B+ voltage to see it is at the values specified.
7.
Check the antenna terminals, metal trim, "metallized" knobs,
screws, and all other exposed metal parts for AC leakage.
Check leakage as described below.
LEAKAGE TEST
The AC leakage from any exposed metal part to earth ground and
from all exposed metal parts to any exposed metal part having a
return to chassis, must not exceed 0.5mA (500 microampers).
Leakage current can be measured by any one of three methods.
1.
A commercial leakage tester, such as the Simpson 229 or RCA
TW-540A. Follow the manufacturers' instructions to use these
instruments.
2.
A battery-operated AC milliammeter. The Data Precision 245
digital multimeter is suitable for this job.
3.
Measuring the voltage drop across a resistor by means of a
VOM or battery-operated AC voltmeter. The "limit" indication
is 0.75V, so analog meters must have an accurate low voltage
scale. The Simpson 250 and Sanwa SH-63Trd are examples
of a passive VOM that is suitable. Nearly all battery operated
digital multimeters that have a 2V AC range are suitable. (See
Fig. A)
To Exposed Metal
Parts on Set
0.15
µF
1.5 k
AC
Voltmeter
(0.75 V)
Earth Ground
Fig. A. Using an AC voltmeter to check AC leakage.


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SERVICE NOTE
1.
ERROR CODE INDICATION ··········································· 6
2.
HOW TO REPLACE A ROTARY UPPER DRUM
(777HF, 778HF MODEL) ·················································· 7
2-1.
HOW TO REMOVE A ROTARY UPPER DRUM ············ 7
2-2.
HOW TO ATTACH A NEW ROTARY
UPPER DRUM ··································································· 7
1.
GENERAL
Getting Started
Unpacking ·············································································· 1-1
Setting up the remote commander ········································· 1-1
Hookups ················································································· 1-1
Selecting a language ······························································ 1-7
Setting the clock ···································································· 1-7
Setting up cable box control ·················································· 1-9
Presetting channels ······························································ 1-10
Setting up VCR Plus+ ·························································· 1-11
Basic Operations
Playing a tape ······································································· 1-12
Recording TV programs ······················································ 1-13
Recording TV programs using VCR Plus+ ························· 1-14
Setting the timer manually ··················································· 1-14
Additional Operations
Playing/searching at various speeds ···································· 1-15
Searching for a selected point on the tape ··························· 1-16
Skip-searching automatically ··············································· 1-16
Recording TV programs using the quick timer ··················· 1-16
Checking/changing/cancelling timer settings ······················ 1-17
Recording stereo and bilingual programs ···························· 1-17
Adjusting the picture ··························································· 1-18
Changing menu options ······················································· 1-18
Editing with another VCR ··················································· 1-18
Additional Information
General setup information ··················································· 1-19
Index to parts and controls ··················································· 1-19
2.
DISASSEMBLY
2-1.
UPPER CASE,
FRONT PANEL BLOCK ASSEMBLY ·························· 2-1
2-2.
FR-138 BOARD, DM-80 BOARD ································· 2-1
2-3.
REAR PANEL ································································· 2-1
2-4.
POWER BLOCK, MA-327 BOARD (WITH S
MECHANISM DECK) ··················································· 2-2
2-5.
S MECHANISM DECK ················································· 2-2
2-6.
INTERNAL VIEWS ························································ 2-3
2-7.
CIRCUIT BOARDS LOCATION ··································· 2-4
3.
BLOCK DIAGRAMS
3-1.
OVERALL BLOCK DIAGRAM ···································· 3-1
3-2.
VIDEO BLOCK DIAGRAM ·········································· 3-3
3-3.
SERVO/SYSTEM CONTROL BLOCK DIAGRAM ····· 3-5
3-4.
AUDIO BLOCK DIAGRAM ·········································· 3-7
3-5.
MODE CONTROL BLOCK DIAGRAM ······················· 3-9
3-6.
TUNER BLOCK DIAGRAM ······································· 3-11
3-7.
POWER SUPPLY BLOCK DIAGRAM ······················· 3-13
4.
PRINTED WIRING BOARDS AND
SCHEMATIC DIAGRAMS
4-1.
FRAME SCHEMATIC DIAGRAM ································ 4-1
4-2.
PRINTED WIRING BOARDS AND
SCHEMATIC DIAGRAMS ············································ 4-3
· MA-327 (REC/PB AMP, VIDEO, SERVO/SYSTEM
CONTROL, AUDIO, TUNER)
PRINTED WIRING BOARD ························· 4-3
· MA-327 (REC/PB AMP)
SCHEMATIC DIAGRAM ······························ 4-5
· MA-327 (VIDEO, NORMAL AUDIO)
SCHEMATIC DIAGRAM ······························ 4-8
· MA-327 (SERVO/SYSTEM CONTROL)
SCHEMATIC DIAGRAM ···························· 4-11
· MA-327 (ON SCREEN DISPLAY)
SCHEMATIC DIAGRAM ···························· 4-15
· MA-327 (AFM AUDIO)
SCHEMATIC DIAGRAM ···························· 4-17
· MA-327 (TUNER)
SCHEMATIC DIAGRAM ···························· 4-19
· MA-327 (POWER SUPPLY, AV BUS)
SCHEMATIC DIAGRAM ···························· 4-21
· FR-138 (MODE CONTROL)
PRINTED WIRING BOARD ······················· 4-23
· FR-138 (MODE CONTROL)
SCHEMATIC DIAGRAM ···························· 4-25
· DM-80 (OPERATION SWITCHES)
PRINTED WIRING BOARD AND
SCHEMATIC DIAGRAM ···························· 4-27
· JK-162 (LINE-2 IN)
PRINTED WIRING BOARD AND
SCHEMATIC DIAGRAM ···························· 4-28
· POWER BLOCK SR801 (SWITCHING REGULATOR)
PRINTED WIRING BOARD AND
SCHEMATIC DIAGRAM ···························· 4-29
· POWER BLOCK SR709 (SWITCHING REGULATOR)
PRINTED WIRING BOARD AND
SCHEMATIC DIAGRAM ···························· 4-31
5.
INTERFACE,
IC PIN FUNCTION DESCRIPTION
5-1.
SYSTEM CONTROL --
MECHANISM BLOCK INTERFACE
(MA-327 BOARD IC160) ··············································· 5-1
5-2.
SYSTEM CONTROL --
SERVO PERIPHERAL CIRCUIT INTERFACE
(MA-327 BOARD IC160) ··············································· 5-1
5-3.
SYSTEM CONTROL -- SYSTEM CONTROL
PERIPHERAL CIRCUIT INTERFACE
(MA-327 BOARD IC160) ··············································· 5-2
5-4.
SYSTEM CONTROL AND RF MODULATOR--
INPUT SELECTION BLOCK INTERFACE
(MA-327 BOARD IC160) ··············································· 5-2
5-5.
SYSTEM CONTROL --
VIDEO/RP BLOCK INTERFACE
(MA-327 BOARD IC160) ··············································· 5-2
5-6.
SYSTEM CONTROL --
AUDIO BLOCK INTERFACE
(MA-327 BOARD IC160) ··············································· 5-2
5-7.
SERVO/SYSTEM CONTROL MICROPROCESSOR
(MA-327 BOARD IC160) ··············································· 5-3
6.
ADJUSTMENTS
6-1
MECHANICAL ADJUSTMENTS ································· 6-1
6-2.
ELECTRICAL ADJUSTMENTS ··································· 6-1
2-1.
PREPARATION BEFORE ADJUSTMENT ··················· 6-1
2-1-1. Equipment Required ························································ 6-1
2-1-2. Equipment Connection ···················································· 6-1
2-1-3. Input Signal Check ·························································· 6-1
2-1-4. Alignment Tape ······························································· 6-1
2-1-5. Input/Output Levels and Impedance ······························· 6-2
2-1-6. Adjustment Sequence ······················································ 6-2
2-2.
POWER SUPPLY CHECK ············································· 6-2
2-2-1. Output Voltage Check (MA-327 Board) ························· 6-2
2-3.
SERVO SYSTEM CHECK ············································· 6-3
2-3-1. RF Switching Position/
AF Switching Position Adjustments (MA-327 Board) ··· 6-3
TABLE OF CONTENTS


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2-4.
VIDEO SYSTEM CHECKS ··········································· 6-4
2-4-1. X'tal OSC Check (MA-327 Board) ································· 6-4
2-4-2. SYNC AGC Check (MA-327 Board) ······························ 6-4
2-4-3. Recording Y Level Check (MA-327 Board) ··················· 6-4
2-4-4. Recording Chroma Level Check(MA-327 Board) ·········· 6-5
2-4-5. Playback Level Check (MA-327 Board) ························· 6-5
2-5.
AUDIO SYSTEM ADJUSTMENT ································· 6-5
2-5-1. ACE Head Adjustment ···················································· 6-5
2-5-2. E-E Output Level Check ················································· 6-5
2-5-3. Overall Output Level and Distortion Factor Check ········· 6-6
2-5-4. Overall Noise Level Check ·············································· 6-6
2-6.
TUNER SYSTEM ADJUSTMENT ································ 6-6
2-6-1. Separation Adjustment (MA-327 Board) ························ 6-6
2-7.
ADJUSTING PARTS LOCATION DIAGRAM ············· 6-8
7.
REPAIR PARTS LIST
7-1.
EXPLODED VIEWS ······················································ 7-1
7-1-1. FRONT PANEL ASSEMBLY AND UPPER CASE
SECTION ········································································ 7-1
7-1-2. CHASSIS SECTION ······················································· 7-2
7-1-3. MECHANISM DECK-1 ················································· 7-3
7-1-4. MECHANISM DECK-2 ················································· 7-4
7-1-5. MECHANISM DECK-3 ················································· 7-5
7-2.
ELECTRICAL PARTS LIST ·········································· 7-6